var http = require('http');
var https = require('https');
var url = require("url");
var pass = require('stream').PassThrough;

var getHeader = function (req) {
    var ret = {};
    for (var i in req.headers) {
        if (!/^(host|connection|Access-|origin|referer|user-agent|user-doclever|path-doclever|url-doclever|method-doclever|headers-doclever|X-Requested-With)/i.test(i)) {
            ret[i] = req.headers[i];
        }
    }
    ret["accept"] = "*/*";
    var headers = req.headers["headers-doclever"];
    if (headers) {
        headers = JSON.parse(headers);
        for (var key in headers) {
            ret[key] = headers[key];
        }
    }
    return ret
};

var filterResHeader = function (headers, res) {
    var ret = {};
    res.setHeader("Cache-Control", "no-cache,no-store");
    res.setHeader("Pragrma", "no-cache");
    res.setHeader("Expires", 0);
    var resHeaders = res.getHeader("Access-Control-Expose-Headers") ? res.getHeader("Access-Control-Expose-Headers").toLowerCase() : "";
    for (var i in headers) {
        if (!/Access-/i.test(i)) {
            if (/set-cookie/i.test(i)) {
                for (let index = 0; index < headers[i].length; index++) {
                    headers[i][index] = headers[i][index].split(" ")[0];
                }
                ret[i] = headers[i];
            } else {
                ret[i] = headers[i];
            }
        }
        if (!resHeaders) {
            res.setHeader("Access-Control-Expose-Headers", i);
        } else if (resHeaders.indexOf(i.toLowerCase() + ",") == -1 && resHeaders.indexOf("," + i.toLowerCase()) == -1) {
            res.setHeader("Access-Control-Expose-Headers", res.getHeader("Access-Control-Expose-Headers") + "," + i);
        }
    }
    return ret;
};

var getPath = function (req) {
    var url = req.url;
    if (url.substr(0, 7).toLowerCase() === 'http://') {
        var i = url.indexOf('/', 7);
        if (i !== -1) {
            url = url.substr(i);
        }
    }
    return url;
};

function getHost(req) {
    var url = req.headers["url-doclever"];
    url = url.replace(/^(http:\/\/|https:\/\/)/i, "");
    var arr = url.split(":");
    return arr[0];
}

function getPort(req) {
    var url = req.headers["url-doclever"];
    var defaultPort;
    if (req.headers["url-doclever"].toLowerCase().startsWith("https://")) {
        defaultPort = 443;
    } else {
        defaultPort = 80;
    }
    url = url.replace(/^(http:\/\/|https:\/\/)/i, "");
    var arr = url.split(":");
    return arr.length > 1 ? arr[1] : defaultPort;
}

var onProxy = function (req, res) {
    handleHeader(req, res);
    if (req.method == "OPTIONS") {
        return;
    }
    if (!req.headers["url-doclever"]) {
        mock(req, res);
    } else {
        proxy(req, res);
    }
};

function mock(req, res) {
    var obj = url.parse(mockUrl);
    var path = req.headers.path || url.parse(req.url).path;
    var opt = {
        host: obj.hostname,
        path: (obj.pathname == "/" ? "" : obj.pathname) + path,
        method: req.method,
        headers: getHeader(req),
        port: obj.port ? obj.port : 80,
    }
    console.log("初次请求：method:" + opt.method + "host:" + opt.host + "port:" + opt.port + "path:" + opt.path)
    if (opt.headers["content-length"]) {
        delete opt.headers["content-length"]
    }
    var req2 = http.request(opt, function (res2) {
        if (!realUrl || res2.headers["finish-doclever"] == "0") {
            console.log("接口开发中，返回mock数据");
            res.writeHead(res2.statusCode, filterResHeader(res2.headers, res));
            res2.pipe(res);
            res2.on('end', function () {

            });
        } else {
            if (res2.headers["finish-doclever"] == "1") {
                console.log("接口已完成，调用真实接口");
            } else {
                console.log("接口或者项目未找到，转调真实接口");
            }
            var headers = getHeader(req);
            var objUrl = url.parse(realUrl);
            var request1, opt1;
            if (objUrl.protocol == "http:") {
                opt1 = {
                    host: objUrl.hostname,
                    path: (objUrl.pathname == "/" ? "" : objUrl.pathname) + path,
                    method: req.method,
                    port: objUrl.port ? objUrl.port : 80,
                    headers: headers
                }
                request1 = http.request;
            } else {
                opt1 = {
                    host: objUrl.hostname,
                    path: (objUrl.pathname == "/" ? "" : objUrl.pathname) + path,
                    method: req.method,
                    port: objUrl.port ? objUrl.port : 443,
                    headers: headers,
                    rejectUnauthorized: false,
                    requestCert: true,
                }
                request1 = https.request;
            }
            console.log("调用真实接口：method:" + opt1.method + "host:" + opt1.host + "port:" + opt1.port + "path:" + opt1.path)
            var req3 = request1(opt1, function (res3) {
                console.log("真实接口调用完成。status:" + res3.statusCode)
                res.writeHead(res3.statusCode, filterResHeader(res3.headers, res));
                res3.pipe(res);
                res3.on('end', function () {

                });
            })
            if (/POST|PUT/i.test(req.method)) {
                stream.pipe(req3);
            } else {
                req3.end();
            }
            req3.on('error', function (err) {
                res.end(err.stack);
            });
        }
    });
    var stream;
    if (/POST|PUT|PATCH/i.test(req.method)) {
        stream = new pass();
        req.pipe(stream);
        req.pipe(req2);
    } else {
        req2.end();
    }
    req2.on('error', function (err) {
        res.end(err.stack);
    });
}

function handleHeader(req, res) {
    if (!req.headers.origin) {
        return;
    }
    res.setHeader("Access-Control-Allow-Origin", req.headers.origin);
    res.setHeader("Access-Control-Allow-Headers", "X-Requested-With");
    res.setHeader("Access-Control-Allow-Methods", "PUT,POST,GET,DELETE");
    res.setHeader("Access-Control-Allow-Credentials", "true");
    if (req.headers["access-control-request-headers"]) {
        res.setHeader("Access-Control-Allow-Headers", req.headers["access-control-request-headers"])
    }
    res.setHeader("Access-Control-Expose-Headers", "connection,content-length,date,x-powered-by,content-encoding,server,etag,accept-ranges,allow,content-language,set-cookie,doclever-request");
    if (req.method == "OPTIONS") {
        res.writeHead(200, {
            'Content-Type': 'text/plain'
        });
        res.end();
        return;
    }
}

function redirect(res, bHttps, opt, location) {
    var urlRedirect = location;
    if (urlRedirect.startsWith("/")) {
        urlRedirect = (bHttps ? "https://" : "http://") + opt.host + ":" + opt.port + urlRedirect;
    }
    var objUrl = url.parse(urlRedirect);
    var request1, opt1;
    if (objUrl.protocol == "http:") {
        opt1 = {
            host: objUrl.hostname,
            path: objUrl.path,
            method: "GET",
            port: objUrl.port ? objUrl.port : 80,
        }
        request1 = http.request;
        bHttps = false;
    } else {
        opt1 = {
            host: objUrl.hostname,
            path: objUrl.path,
            method: "GET",
            port: objUrl.port ? objUrl.port : 443,
            rejectUnauthorized: false,
            requestCert: true,
        }
        request1 = https.request;
        bHttps = true;
    }
    var req3 = request1(opt1, function (res3) {
        if (res3.statusCode == 302) {
            redirect(res, bHttps, opt, res3.headers.location)
        } else {
            var resHeader = filterResHeader(res3.headers, res)
            resHeader["doclever-request"] = JSON.stringify(handleSelfCookie(req3));
            res.writeHead(res3.statusCode, resHeader);
            res3.pipe(res);
            res3.on('end', function () {

            });
        }
    })
    req3.end();
    req3.on('error', function (err) {
        res.end(err.stack);
    });
}

function handleSelfCookie(req) {
    var arr = req._headers;
    arr["url"] = req.method + " " + req.path;
    var cookie = arr["cookie"];
    if (!cookie) {
        return arr;
    }
    var arrCookie = cookie.split(";");
    var keys = ["id", "name", "photo", "qq", "sex", "company", "phone", "loginCount", "age", "email"];
    arrCookie = arrCookie.filter(function (obj) {
        obj = obj.trim();
        for (let key of keys) {
            if (obj.startsWith(key + "=")) {
                return false;
            }
        }
        return true;
    })
    arr["cookie"] = arrCookie.join(";");
    return arr;
}

function proxy(req, res) {
    var bHttps = false;
    if (req.headers["url-doclever"].toLowerCase().startsWith("https://")) {
        bHttps = true;
    }
    var opt, request;
    if (bHttps) {
        opt = {
            host: getHost(req),
            path: req.headers["path-doclever"],
            method: req.headers["method-doclever"],
            headers: getHeader(req),
            port: getPort(req),
            rejectUnauthorized: false,
            requestCert: true,
        };
        request = https.request;
    } else {
        opt = {
            host: getHost(req),
            path: req.headers["path-doclever"],
            method: req.headers["method-doclever"],
            headers: getHeader(req),
            port: getPort(req)
        };
        request = http.request;
    }
    var req2 = request(opt, function (res2) {
        if (res2.statusCode == 302) {
            redirect(res, bHttps, opt, res2.headers.location)
        } else {
            var resHeader = filterResHeader(res2.headers, res)
            resHeader["doclever-request"] = JSON.stringify(handleSelfCookie(req2));
            res.writeHead(res2.statusCode, resHeader);
            res2.pipe(res);
            res2.on('end', function () {

            });
        }
    });
    if (/POST|PUT|PATCH/i.test(req.method)) {
        req.pipe(req2);
    } else {
        req2.end();
    }
    req2.on('error', function (err) {
        res.end(err.stack);
    });
}

var arguments = process.argv.splice(2);
var mockUrl = arguments[0];
var realUrl = arguments[1];
var port = arguments[2] ? arguments[2] : 8082;
var server = http.createServer(onProxy);
server.listen(port);
console.log(arguments.length > 0 ? ("内网测试，Mock数据正监听端口：" + port) : "正在运行中，请用DOClever的接口测试页面进行内网测试！");
